It is known that fixtures, appliances and devices not regularly classified as plumbing fixtures may be drained by indirect means if they are provided with drip or drainage outlets. Appliances of this type include refrigerators, ice boxes, bar sinks, automatic ice makers, drinking fountains, cooling or refrigerating coils, laundry washers, extractors, steam tables, egg boilers, coffee urns, stills, sterilizers, water stations, water lifts, expansion tanks, cooling jackets, drip or overflow pans, air conditioning condensate drains, drains from overflows, and relief vents from the water supply system.
Such indirect drainage, which is almost universally required in building codes within the United States, is intended to prevent bacteria from backing-up from sewage lines into these special fixtures and from contaminating their contents. For example, overflow and relief pipes on expansion tanks, such as sprinkler systems, and cooling jackets must always be indirectly connected to the sanitary drainage system. This avoids the possibility of a cross-connection which would contaminate the potable water supply system. A positive separation by indirect means, i.e., a physical distance between the waste drain inlet and the indirect drainage outlet of appliances of the above type and of hospital equipment.
The so-called indirect method of piping is unique and is most practical for fixtures with low discharge rates. While some building codes do not require specified horizontal lengths for indirect waste piping, others impose a maximum length of fifteen feet. Also, the required positive separation between the appliance fixture outlet and the waste drain input typically varies between one inch and two inches. The basic problem in indirect waste piping is that the horizontal length of the piping, in combination with the gravity vector, gives rise to a moment of rotation of the outlet piping of the indirect drain. Thereby, over time, the indirect waste piping exhibits a tendency to droop, in some instances to the point that the required positive separation between the outlet of the indirect waste piping and the drainage inlet is compromised. This, for the reasons above set forth above can pose a serious hazard to the contents of the consumer or hospital appliance or the type enumerated above. It is accordingly, in response to this problem that the present invention is directed.
To the knowledge of the inventor, the hereinafter set forth response to the above problem is completely novel.